# Effects of late first language acquisition on phonological processing in American Sign Language

> **NIH NIH F31** · UNIVERSITY OF CALIFORNIA, SAN DIEGO · 2024 · $41,783

## Abstract

Project Summary
 Only around 5% of deaf children are born to deaf parents and subsequently get exposure to an
accessible sign language as their first language from birth (Mitchell & Karchmer, 2004). The other 95% of deaf
children are born into hearing families and are at high risk of late first language acquisition that occurs after
the critical period for language (Lenneberg, 1967). As adults, this late first language acquisition results in
dramatic and lifelong effects on everything from education to job opportunities to mental health (Hall, 2017).
Research looking at the effects of late first language acquisition on language in particular shows effects on
language outcomes and neurolinguistic processing at the word and sentence levels (e.g., Mayberry & Kluender,
2018). The preliminary data of this project show that late first language acquisition also affects the sub-word
level, known as the phonological level (Nielson & Mayberry, in review).
 When processing the phonology of a sign language, one must visually perceive and manually articulate
forms categorized into handshapes, movements, locations, and palm orientations. These categories are referred
to as parameters and native signers who acquire ASL from birth exhibit specific patterns of the parameters in
their productions and perceptual judgments (e.g., Conlin et al., 2000; Hildebrandt & Corina, 2002).
Understanding these parameter patterns provides insight into how native signers process phonology, which is
important for fully understanding language processing. Thus, investigating how late L1 signers process
phonology is crucial for fully understanding the effects of late first language acquisition on language. The
completed first study of this project looked at phonological production and found that late first language
signers exhibit a different pattern of parameter errors when compared to native signers. The proposed studies
look at phonological perception behaviorally to better understand the systematic effects of late first language
acquisition on phonological processing across production and perception (Aim 1), as well as neurolinguistically
to identify the impact of late first language acquisition on the loci and time course of phonological processing in
the brain (Aim 2). The ultimate goal of this project is to determine the relationship between the behavioral
outcomes and the neurolinguistic processing in the brain (Aim 3) to better understand the causes of disordered
communication for deaf late L1 signers and prevent them.
 Identifying the impact of late first language acquisition on phonological processing behaviorally and
neurolinguistically is crucial for a greater characterization of the communication of deaf individuals and a
deeper understanding of the brain causes associated with normal function and disordered processes of
communication. This project will also enhance the applicant’s research training and greatly improve her ability
to transition from a graduate student t...

## Key facts

- **NIH application ID:** 10899897
- **Project number:** 1F31DC021854-01
- **Recipient organization:** UNIVERSITY OF CALIFORNIA, SAN DIEGO
- **Principal Investigator:** Shai Lynne Nielson
- **Activity code:** F31 (R01, R21, SBIR, etc.)
- **Funding institute:** NIH
- **Fiscal year:** 2024
- **Award amount:** $41,783
- **Award type:** 1
- **Project period:** 2024-01-01 → 2025-12-31

## Primary source

NIH RePORTER: https://reporter.nih.gov/project-details/10899897

## Citation

> US National Institutes of Health, RePORTER application 10899897, Effects of late first language acquisition on phonological processing in American Sign Language (1F31DC021854-01). Retrieved via AI Analytics 2026-05-24 from https://api.ai-analytics.org/grant/nih/10899897. Licensed CC0.

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